In the field of food or beverage preparation, it is known to use single-serve capsules for mixing a precursor ingredient contained in said capsule, with a mixing ingredient fed from a pressurized source contained in a food or beverage preparation machine.
Generally, food or beverage preparation machines are well known in the food science and consumer goods area. Such machines allow a consumer to prepare at home a given type of food or beverage, for instance a coffee-based beverage, e.g. an espresso or a brew-like coffee cup, or other types of beverages like chocolate, teas, soups and the like.
Today, most beverage preparation machines for in-home beverage preparation comprise a system made of a machine which can accommodate portioned ingredients for the preparation of the beverage. Such portions can be soft pods or pads, or sachets, but more and more systems use semi-rigid or rigid portions such as rigid pods or capsules.
The machine comprises a receptacle or cavity for accommodating said capsule and a fluid injection system for injecting a fluid, preferably water, under pressure into the capsule. Water injected under pressure in the capsule, for the preparation of a coffee beverage according to the present invention, is preferably hot, that is to say at a temperature above 70° C. However, in some particular instances, it might also be at ambient temperature, or even chilled. The pressure (relative to atmospheric pressure) inside the container/capsule chamber during extraction and/or dissolution of the capsule contents, until the capsule opens, increases up to typically about 1 to about 8 bar for dissolution products and about 2 to about 12 bar for extraction of roast and ground coffee. Such a preparation process differs a lot from the so-called “brewing” process of beverage preparation—particularly for tea and coffee, in that brewing involves a long time of infusion of the ingredient by a fluid (e.g. hot water), whereas the beverage preparation process allows a consumer to prepare a beverage, for instance coffee, within a few seconds.
The principle of extracting and/or dissolving the contents of a closed capsule under pressure is known, and consists typically of inserting the capsule in a receptacle or cavity of a machine, injecting a quantity of pressurized water into the capsule, generally after piercing a face of the capsule with a piercing injection element such as a fluid injection needle mounted on the machine, so as to create a pressurized environment inside the capsule either to extract the substance or dissolve it, and then release the extracted substance or the dissolved substance through the capsule. Capsules allowing the application of this principle have already been described for example in applicant's European patents no EP 1472156 B1, and EP 1784344 B1.
Machines allowing the application of this principle have already been described for example in patents CH 605 293 and EP 242 556. According to these documents, the machine comprises a receptacle or cavity for the capsule and a perforation and injection element made in the form of a hollow needle comprising in its distal region one or more liquid injection orifices. The needle has a dual function in that it opens the top portion of the capsule on the one hand, and that it forms the water inlet channel into the capsule on the other hand.
The machine further comprises a fluid tank—in most cases this fluid is water—for storing the fluid that is used to dissolve and/or infuse and/or extract under pressure the ingredient(s) contained in the capsule. The machine comprises a heating element such as a boiler or a heat exchanger, which is able to warm up the water used therein to working temperatures (classically temperatures up to 80-90° C.). Finally, the machine comprises a pump element for circulating the water from the tank to the capsule, optionally though the heating element. The way the water circulates within the machine is e.g. selected via a selecting valve means, such as for instance a peristaltic valve of the type described in applicant's European patent EP 2162653 B1.
When the beverage to be prepared is coffee, one interesting way to prepare the coffee is to provide the consumer with a capsule containing roast and ground coffee powder, which is to be extracted with hot water injected therein.
In many instances, the machine comprises a capsule holder for holding a capsule, which is intended to be inserted in and removed from a corresponding cavity or receptacle of the machine. When a capsule holder is loaded with a capsule and inserted within the machine in a functional manner, the water injection means of the machine can fluidly connect to the capsule to inject water therein for a food preparation, as described above. A capsule holder was described for example in applicant's European patent EP 1967100 B1.
Capsules have been developed for such an application of food preparation, and in particular for beverage preparation, which are described and claimed in applicant's European patent EP 1784344 B1, or in European patent application EP 2062831.
In short, such capsules comprise typically:
a hollow body and an injection wall which is impermeable to liquids and to air and which is attached to the body and adapted to be punctured by e.g. an injection needle of the machine,
a chamber containing a bed of roast and ground coffee to be extracted, or a soluble ingredient or mix of soluble ingredients,
an aluminium membrane disposed at the bottom end of the capsule, closing the capsule, for retaining the internal pressure in the chamber.
The aluminium membrane is designed for being pierced with piercing means that are either integral with the capsule, or located outside of said capsule, for example within a capsule holder of the machine.
The piercing means are adapted for piercing dispensing holes in the aluminium membrane when the internal pressure inside the chamber reaches a certain pre-determined value.
Also, optionally, the capsule can further comprise means configured to break the jet of fluid so as to reduce the speed of the jet of fluid injected into the capsule and distribute the fluid across the bed of substance at a reduced speed.
In many food and beverage preparation systems, several types of containers (such as capsules) can be used with the same machine. Some capsules can be used for infusion of a stationery precursor ingredient (e.g. roast and ground coffee) through which the mixing ingredient (e.g. hot water) flows. Some other capsules may also contain a soluble precursor ingredient, such as a soluble milk or chocolate powder, which is dissolved by mixing with a mixing ingredient like hot water.
In known food and beverage systems, the food or beverage preparation is equipped with a pump that withdraws the mixing fluid (typically water) from the machine reservoir and displaces it through the fluid pipe system of the machine towards the capsule wherein said water is injected.
EP 2236437 A1 is a European patent publication that discloses a capsule for use in a beverage production device, the capsule containing ingredients to produce a nutritional or food liquid when a liquid is fed into the capsule at an inlet face thereof, the capsule being provided with a filter having a plurality of filtering orifices, wherein it comprises a flow collection member placed downstream of the filter to collect the filtered liquid from the filtering orifices. The collection member comprises at least one restriction orifice to focus the flow of liquid in at least one jet of liquid at high velocity in the compartment containing the ingredients. The invention is particularly advantageous for producing a nutritional liquid (e.g., infant formula) or a food from powdered ingredients, when used with a machine able to inject water therein, by means of a pump placed within said machine.
WO 2012/104760 is a PCT application that discloses a capsule comprising a deformable and/or compressible casing, provided with a base wall and with a side wall defining a cavity that is open and suitable for containing an initial product to obtain a final food product, a supporting element fixed to a first edge of said casing and facing said cavity; the capsule further comprises a nozzle that is fixed to the supporting element and arranged for delivering into the cavity a fluid interacting with the initial product to make the final product, and for opening the base wall and enabling the final product to exit when the casing is compressed and crushed. The capsule is intended for use with a machine able to inject a fluid such as water therein by means of a fluid pump placed within said machine.
US 2010 203198 is a US application disclosing a single-use capsule for preparing a food liquid from a food substance contained in the capsule by introducing water in the capsule and passing water through the substance using the centrifugal forces for producing the food liquid which is centrifuged peripherally in the capsule relatively to a central axis of the capsule corresponding to an axis of rotation during the centrifugation. The water injected within said capsule is introduced by a beverage machine to which said capsule is connected, said machine comprising a water pump.
WO 2011 117768 A capsule for making a drink comprises a cup-shaped main body forming a housing chamber containing a powdered or liquid substance. The capsule is meant to be connected to a beverage machine that has a pump for injecting water into the capsule for forming a beverage.
For the sake of clarity, a “pump” is defined within the meaning of the present invention as “a device that converts mechanical energy into fluid energy by any various technologies, typically by suction or compression, in order to move water, air, or other fluids into, through, or out of a system”. Typically in the known food or beverage preparation systems, the pump contained in the machine is actuated by an electric motor, and converts mechanical energy brought by said electric motor, into fluid energy that circulates water from the machine reservoir to the capsule, as described above. The pumps used in food or beverage preparation machines are typically piston pumps using solenoid technology.
The fact that water passes through the pump of the machine leads to scaling of the internal elements of the pump. In case the user does not properly descale the machine, the pump can stop working and the user needs to call for technical assistance or change the machine. Furthermore, pumps used in the known food or beverage preparation systems today are noisy as they are subject to vibrations throughout the pipe system of the machine. And most of them are expensive too.
It is therefore an objective of the present invention to provide a food or beverage system that obviates the drawbacks mentioned above.